Arc discharge lamps

ABSTRACT

A method of mounting an arc tube, having pinch seals, between two parallel struts by using a staple having a bar with two legs, passing the legs through the plane of the struts, and binding the legs back around the struts to secure the arc tube thereto.

United States Patent Kenneth Scott;

Dennis A. Ramsey, London, England 696,023

Jan. 5, l 968 May 4, 1971 British Lighting Industries Limited London, England Jan. 17, 1967 Great Britain Inventors Appl. No. Filed Patented Assignee Priority ARC DISCHARGE LAMPS 5 Claims, 4 Drawing Figs.

US. Cl 29/25.l5, 29/25.13 Int. Cl H0lj 9/18,

HOlj 9/36 [50] Field of Search 29/25.l3,

- .14,.l5,432,;3l3/3l5 [56] References Cited UNITED STATES PATENTS 2,624,100 l/l953 Foulkes 29/25. 14 2,943,228 6/1960 Kleinman 315/35 3,154,113 10/1964 Mogsker..................... l40/7l.5 3,218,690 ll/1965 Gartner 29/25. 14 3,383,542 5/1968 Van Der Jagt et al. 313/350 Primary Examiner-John F. Campbell Assistant ExaminerRichard Bernard Lazarus Attorneys-Owen J. Meegan and Laurence Burns ABSTRACT: A method of mounting an arc tube, having pinch seals, between two parallel struts by using a staple having a bar with two legs, passing the legs through the plane of the struts, and binding the legs back around the struts to secure the arc tube thereto.

PATENTEU W 41971 INVENTORS NETH SCOTT NIS ARTHUR RAMSEY KEN DEN BY 0 A ORNE ARC DISCHARGE LAMPS v The invention relates to are discharge lamps and, in particular, to the support of the arc tubes of such lamps.

The are tubes of arc discharge lamps are generally supported on'a wire frame within an outer lamp envelope.

According to the present invention in one form there is provided a method of mounting the arc tube of an arc discharge lamp wherein the arc tube is dispersed between two parallel struts of a frame with the pinch seals of the tube in the plane of the struts, and a staple of resilient material is applied in the region of a seal in such a manner that the legs of the staple pass through the plane of the struts outside the struts and are then pressed against an abutment surface to bend them back inwardly around the struts and against the seal to locate and grip the seal.

' According to the invention in another form the frame is provided with cross-struts against which the seals of the arc tube lie and the legs of the staple are passed between the struts and the seal and bent back outwardly around the-struts to locate and grip the seal between the staple and one of the crossstruts.

An embodiment of the invention will be described with reference to the accompanying drawings in which:

FIG. 1 shows an arc tube of a mercury vapor arc discharge lamp mounted upon a frame by a first method in accordance with the present invention,

FIG. 2 is a section taken along the line ll-ll in FIG. 1,

H6. 3 is a section similar to that of FIG. 2 showing a second method of mounting in accordance with the present invention, and

FIG. 4 is a schematic cross section of the apparatus used in the first method of mounting at one stage of manufacture.

FIG. 1 shows a metal frame supported at one end on a press of an outer envelope (not shown) and having at the other end a clip 11 for engagement with a dimple on the outer'envelope in conventional manner. The frame has two parallel struts or side members 12 and 13 and cross-struts 14 and 15 welded to the'side members 12 and 13. A conventional quartz arc tube 16 having pinch seals 17 and 18 is located between the side members 12 and 13 with the seals 17 and 18 in the plane of the struts and lying against the cross-struts 14 and 15 respectively. The seals 17 and 18 are held in position by staples 19 and 20, respectively, which have their ends wrapped around the struts or side members 12 and 13 as shown in FIG.

2. Ridges 21 and 22 formed on the pinch seals 17 and 18 serve to locate the arc tube axially and prevent contact of any part of the metal frame with the outer surface of the tube 16 surrounding the discharge space.

The tube 16 has conventional tungsten coil electrodes 23 and 24 connected by molybdenum foils 25 and 26 within the pinch seals 17 and 18, respectively, to leads 27 and 28, respectively. The lead 27 is attached to the frame which in turn is attached to a conductor 29 passing through the press 10 to the lamp cap. The lead 28 is connected directly to a second conductor 30 passing through the press 10. A starter electrode 31 extends into the tube 16 from a foil 32 in the pinch seal 18, the foil being connected to the frame through a lead 33 and a resistor 34.

The staples 19 and are applied in a manner similar to that used in applying staples to papers to secure them together.

FIG. 4 illustrates the application of the staple 19 which is made of resilient wire or strip. The pinch seal 17 tests on a displaceable abutment 35 .which is resiliently supported by springs 36 and a recess 37 in a table 38. The staple 19 is driven 5 down a groove 39 by a driver plate 40 so that the legs 41 and 42 of the staple pass on either side of the seal 17 and between the seal 17 and the struts or side. members 12 and 13 of the frame. The abutment 35 has cam or guide surfaces 43 and 44 which splay the legs 41 and 42 outwards. Continued pressure by the driver plate 40 presses the assembly into the recess 37 and the walls of the recess turn the ends of the legs 41 and 42 back against the outside of the members 12 and 13 as shown in FIG. 2. The walls of the recess 37 are chamfered at 45 and 46 to enggga the ends of the legs 41 and 42 after 11% have been splay y the cam or guide surfaces 43 and 44.- e seal 1715 thus gripped firmly and centrally between the cross-strut 14 and the resilient staple 19.

An alternative embodiment of the invention is illustrated in FIG. 3. In this case the cross-struts 14 and 15 are omitted and the arc tube 16 is secured to the side members 12 and 13 of the frame solely by staples 47 which engage each of the pinch seals 17 and 18. The legs 48 and 49 of a staple 47 are passed around the outside of the frame members 12 and 13 and bent inwards'by engagement against a suitably shaped abutment so that they press against the side of the seal 17, the other face of which is engaged by the bar of the staple.

in each of the methods described the resilience of the staple assists in centering the arc tube within the frame and provides a mounting having a high resistance to physical shock.

We claim:

l. A method of mounting an arc tube of an arc discharge lamp comprising the steps of v 5 providing an arc tube having pinch seals disposing the arc tube betweentwo parallel struts of a frame with the pinch seals of the tube in the plane of the struts advancing a resilient staple towards the region of a pinch seal, the staple having a bar and two legs extending from said bar, passing the legs of said staple through the plane of the struts, and bending the legs back around the struts to secure the arc tube to the struts:

2. A method as claimed in claim 1 including the initial step of securing cross-struts to said frame, the arc tube being then disposed with its seals against said cross-struts,.

the legs of the staple being passed between the seal and the struts, and

the legs being then splayed outwardly and bent back around the struts to grip the seal between a cross-strut and the bar of the staple.

3. A method as claimed in claim 1 comprising the step of driving the legs of said staple against a resilient abutment surface after passing them through the plane of the struts.

4. A method as claimed in claim 2 comprising the step of pressing the staple, arc tube, and frame into a recess between sidewalls which thereby bend back the ends of the legs.

5. A method as claimed in claim 4 in which the outward splaying of the legs is performed by driving the legs against a resilient abutment disposed in the recess which'is displaced inwardly when the staple, arc tube, and frame are pressed into the recess. 

1. A method of mounting an arc tube of an arc discharge lamp comprising the steps of providing an arc tube having pinch seals disposing the arc tube between two parallel struts of a frame with the pinch seals of the tube in the plane of the struts advancing a resilient staple towards the region of a pinch seal, the staple having a bar and two legs extending from said bar, passing the legs of said staple through the plane of the struts, and bending the legs back around the struts to secure the arc tube to the struts.
 2. A method as claimed in claim 1 including the initial step of securing cross-struts to said frame, the arc tube being then disposed with its seals against said cross-struts, the legs of the staple being passed between the seal and the struts, and the legs being then splayed outwardly and bent back around the struts to grip the seal between a cross-strut and the bar of the staple.
 3. A method as claimed in claim 1 comprising the step of driving the legs of said staple against a resilient abutment surface after passing them through the plane of the struts.
 4. A method as claimed in claim 2 comprising the step of pressing the staple, arc tube, and frame into a recess between sidewalls which thereby bend back the ends of the legs.
 5. A method as claimed in claim 4 in which the outward splaying of the legs is performed by driving the legs against a resilient abutment disposed in the recess which is displaced inwardly when the staple, arc tube, and frame are pressed into the recess. 